TraCI/Vehicle Signalling

Signaling#

A vehicle's signals are encoded in an integer, each by one bit, encoding whether the according signal/... is on or off. Most signals are rather meant to be used by an external application. However, a few signals are computed in each step.

Computed Signals#

The following signals are computed in each time step. The value set via TraCI is only retained for the current time step.

  • VEH_SIGNAL_BRAKELIGHT: The brake light is set whenever the vehicle is standing (not stopped) or when the vehicle decelerates beyond a threshold value. The signal value is used by the vehicles when trying to avoid jamming on an intersection.
  • VEH_SIGNAL_BLINKER_RIGHT and VEH_SIGNAL_BLINKER_LEFT: The blinker is activated in either of the following conditions
    • The vehicle is about to take a turn at an intersection (activated 7 seconds before reachin the intersection)
    • Either of the continous lane-change models is active
    • A desired lane change cannot be executed due to neighboring vehicles.
  • VEH_SIGNAL_EMERGENCY_BLUE: when switched on, a blinking blue light is shown in the GUI for vehicles with vClass="emergency" and shapeClass="emergency"

Defined Signals#

The following table shows the defined signals.

Name Bit
VEH_SIGNAL_BLINKER_RIGHT 0
VEH_SIGNAL_BLINKER_LEFT 1
VEH_SIGNAL_BLINKER_EMERGENCY 2
VEH_SIGNAL_BRAKELIGHT 3
VEH_SIGNAL_FRONTLIGHT 4
VEH_SIGNAL_FOGLIGHT 5
VEH_SIGNAL_HIGHBEAM 6
VEH_SIGNAL_BACKDRIVE 7
VEH_SIGNAL_WIPER 8
VEH_SIGNAL_DOOR_OPEN_LEFT 9
VEH_SIGNAL_DOOR_OPEN_RIGHT 10
VEH_SIGNAL_EMERGENCY_BLUE 11
VEH_SIGNAL_EMERGENCY_RED 12
VEH_SIGNAL_EMERGENCY_YELLOW 13

Note

Sending a negative signal value immediately resets all signals to their computed values.

See Also#